Technical Field
The present invention relates to a working machine equipped with a relief valve for discharging at least a part of hydraulic oil toward a hydraulic actuator.
Description of Related Art
A shovel equipped with a revolving hydraulic circuit has been known to control drive of a revolving hydraulic motor. This revolving hydraulic circuit includes two high pressure oil passages connected to two ports of the revolving hydraulic motor, and a make-up oil passage for connecting these two high pressure oil passages to hydraulic oil tanks. A high pressure relief valve is arranged between the high pressure oil passages and the make-up oil passage. By this configuration, the revolving hydraulic circuit accelerates the revolving hydraulic circuit by a remaining hydraulic oil while exhausting a part of a hydraulic oil supplied from a hydraulic pump to the hydraulic oil tanks via the high pressure relief valve.